Improvement of optical properties and redox stability of poly(3,4-ethylenedioxythiophene)
By Ertan, Salih; Cihaner, Atilla
Published in Dyes and Pigments
2018
Abstract
In order to improve the optical properties and redox stability of poly(3,4-ethylenedioxythiophene) (PEDOT) without changing its electrochemical and electrochromic behaviour, it was supported with alkyl-substituted polyhedral oligomeric silsesquioxane (POSS) cage. The corresponding copolymers were obtained electrochemically via potentiostatic or potentiodynamic methods and compared to the parent homopolymers. Electrochemical polymerization of {EDOT} and {POSS} containing {EDOT} called EDOT-POSS in various monomer feed ratios was performed in an electrolyte solution of 0.1 M {TBAPF6} dissolved in a mixture of dichloromethane and acetonitrile (1/3: v/v). Just as PEDOT, the copolymers represented the similar band gap (1.61 eV), redox and electrochromic behaviors. On the other hand, when compared to the parent PEDOT, the presence of {POSS} cages in the copolymer backbone improved the redox stability and optical properties of {PEDOT} such as higher percent transmittance change (65% at 621 nm), higher transparency at oxidized state, lower switching time (?1.0 s) and higher coloration efficiency (463 cm2/C for 95% switching) as well as higher electrochemical stability (86% of its electroactivity retains after 1750 cycles under ambient conditions).